de Renzis G, Bornancin M
Biochim Biophys Acta. 1977 Jun 2;467(2):192-207. doi: 10.1016/0005-2736(77)90196-1.
An ATPase is demonstrated in plasma membrane fractions of goldfish gills. This enzyme is stimulated by Cl- and HCO-3, inhibited by SCN-. Biochemical characterization shows that HCO-3 stimulation (Km = 2.5 mequiv./l) is specifically inhibited in a competitive fashion by SCN- (Ki = 0.25 mequiv./l). This residual Mg2+-dependent activity is weakly affected by SCN-. In the microsomal fraction chloride stimulation of the enzyme occurs in the presence of HCO-3 (Km for chloride = 1 mequiv/l); no stimulation is observed in the absence of HCO-3. Thiocyanate exhibits a mixed type of inhibition (Ki = 0.06 mequiv./l) towards the Cl- stimulation of the enzyme. Bicarbonate-dependent ATPase from the mitochondrial fraction is stimulated by Cl-, but this enzyme has a relatively weak affinity for this substrate (Km = 14 mequiv./l).
在金鱼鳃的质膜组分中证实了一种ATP酶。这种酶受Cl-和HCO-3刺激，受SCN-抑制。生化特性表明，HCO-3刺激（Km = 2.5毫当量/升）以竞争性方式被SCN-特异性抑制（Ki = 0.25毫当量/升）。这种残余的Mg2+依赖性活性受SCN-的影响较弱。在微粒体组分中，酶的氯离子刺激在HCO-3存在时发生（氯离子的Km = 1毫当量/升）；在没有HCO-3时未观察到刺激。硫氰酸盐对酶的Cl-刺激表现出混合型抑制（Ki = 0.06毫当量/升）。来自线粒体组分的碳酸氢盐依赖性ATP酶受Cl-刺激，但这种酶对该底物的亲和力相对较弱（Km = 14毫当量/升）。
